6o 
much closer together, being only narrowly separated. The palpi, 
which in 6". calcitrant are exceedingly slender and short, and cannot be 
seen when the insect is viewed from above, in the present species are 
prominent and expanded at the tips, and, though still distinctly 
shorter than the proboscis, are apparently capable of forming a partial 
sheath for that organ. 
The localities of the Museum series of specimens of this common 
species include the Northern Sutor, Cromarty, N.B., and Dartmoor, 
S. Devon ; in addition to various places in the midland and southern 
counties of England, there are also specimens from Barmouth, 
N. Wales, and Kenmare, Co. Kerry, Ireland {Lieut. -Colonel Yerbury). 
The dates of capture range from May 5th to September 6th. For 
Colonel Yerbury's notes, see the previous species. 
The Museum unfortunately possesses no specimens of Hcematobia 
stimulans from localities outside the British Islands, but it is 
probable that on the Continent it is as widely distributed as 
S. calcitrans, although, so far as the writer is aware, it has not 
yet been recorded from any locality outside Europe. Zetterstedt 
states that it occurs throughout Scandinavia, but in Austria, according 
to Schiner, it is somewhat rare. 
Genus 
LYPEROSIA, Rondani. 
Lyperosia irritans, Linn. 
Plate 30, fig. 2. 
In this species, which is by far the smallest of our native blood- 
sucking Muscidae, the female measuring only from 4^ to 5 mm. in 
length, the palpi, as in the Tsetse-flies {Glossina) are flattened from 
side to side and form a complete sheath for the proboscis, which they 
equal in length. Lyperosia irritans does not appear to attack human 
beings, but is a pest of cattle, on the backs of which it is found, showing, 
according to Zetterstedt, a preference for black animals ; this latter 
